(Reuters) - Canadian Eugenie Bouchard has lashed out at the WTA for giving Maria Sharapova the chance to compete in tournaments after serving a 15-month doping ban and said the Russian is a "cheater" who should never be allowed to play again.

Sharapova beat Italian Roberta Vinci in the first round of the Stuttgart Grand Prix on Wednesday after receiving a controversial wild card for the tournament, having lost all her ranking points in the wake of her suspension.

Sharapova was banned for two years after testing positive at the 2016 Australian Open for meldonium, a medication the former world number one had been taking within the rules but which was then reclassified as a banned drug.

The Court of Arbitration for Sport reduced her ban to 15 months, while finding Sharapova was not an "intentional doper" but "bore some degree of fault" for relying on her agent to check the prohibited list for changes and failing to ensure he had done so.

Bouchard, a 2014 Wimbledon finalist, told the Istanbul-based TRT World in an interview that a bad example had been set.

"She's a cheater and ... I don't think a cheater in any sport should be allowed to play that sport again," she said.

"It's so unfair to all the other players who do it the right way and are true. I think from the WTA it sends the wrong message to young kids: 'cheat and we'll welcome you back with open arms'.

"I don't think that's right and (Sharapova is) definitely not someone I can say I look up to any more."

Sharapova, who faces Russia's Ekaterina Makarova in the second round in Stuttgart later on Thursday, has also received invitations to play in Madrid and Rome and will find out in May whether she will be given a wild card for the French Open.